Update jails strategy

[Michael Grimm]

Hi --

[FYI: I am running some service jails with an ezjail-type basejail approach.]

Until now I did stop all jails before updating and restarting them afterwards. Now I am wondering if that is necessary at all. 

Wouldn't it be sufficient to update basejail with running jails and restart them after this updating? (In analogy to a "make installworld; make installkernel; reboot")

Background of my question: Until now I do have two identical servers running in parallel (simple failover approach), but I am thinking about migrating both servers to a single cloud instance, and keeping downtimes of my service jails whilst updating the OS to a bare minimum.

Thanks for your input in advance,
Michael